mirror of
https://github.com/Z3Prover/z3
synced 2025-04-07 01:54:08 +00:00
44679d8f5b
* porting arithmetic solver * integrating arithmetic * lp Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com> * na Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com> * na Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com> * na Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
657 lines
31 KiB
C++
657 lines
31 KiB
C++
/*++
|
|
Copyright (c) 2017 Microsoft Corporation
|
|
|
|
Module Name:
|
|
|
|
<name>
|
|
|
|
Abstract:
|
|
|
|
<abstract>
|
|
|
|
Author:
|
|
Nikolaj Bjorner (nbjorner)
|
|
Lev Nachmanson (levnach)
|
|
|
|
Revision History:
|
|
|
|
|
|
--*/
|
|
#pragma once
|
|
#include "util/vector.h"
|
|
#include <utility>
|
|
#include "util/debug.h"
|
|
#include "util/buffer.h"
|
|
#include <unordered_map>
|
|
#include <unordered_set>
|
|
#include <string>
|
|
#include <algorithm>
|
|
#include <stack>
|
|
#include <functional>
|
|
#include "math/lp/lar_constraints.h"
|
|
#include "math/lp/lar_core_solver.h"
|
|
#include "math/lp/numeric_pair.h"
|
|
#include "math/lp/scaler.h"
|
|
#include "math/lp/lp_primal_core_solver.h"
|
|
#include "math/lp/random_updater.h"
|
|
#include "util/stacked_value.h"
|
|
#include "math/lp/stacked_vector.h"
|
|
#include "math/lp/implied_bound.h"
|
|
#include "math/lp/bound_analyzer_on_row.h"
|
|
#include "math/lp/conversion_helper.h"
|
|
#include "math/lp/int_solver.h"
|
|
#include "math/lp/nra_solver.h"
|
|
#include "math/lp/lp_types.h"
|
|
#include "math/lp/lp_bound_propagator.h"
|
|
|
|
namespace lp {
|
|
|
|
class int_branch;
|
|
class int_solver;
|
|
class lar_solver : public column_namer {
|
|
struct term_hasher {
|
|
std::size_t operator()(const lar_term &t) const
|
|
{
|
|
using std::size_t;
|
|
using std::hash;
|
|
using std::string;
|
|
size_t seed = 0;
|
|
int i = 0;
|
|
for (const auto p : t) {
|
|
hash_combine(seed, (unsigned)p.column());
|
|
hash_combine(seed, p.coeff());
|
|
if (i++ > 10)
|
|
break;
|
|
}
|
|
return seed;
|
|
}
|
|
};
|
|
|
|
struct term_comparer {
|
|
bool operator()(const lar_term &a, const lar_term& b) const
|
|
{
|
|
return a == b;
|
|
}
|
|
};
|
|
|
|
//////////////////// fields //////////////////////////
|
|
lp_settings m_settings;
|
|
lp_status m_status;
|
|
stacked_value<simplex_strategy_enum> m_simplex_strategy;
|
|
// such can be found at the initialization step: u < l
|
|
stacked_value<int> m_crossed_bounds_column;
|
|
lar_core_solver m_mpq_lar_core_solver;
|
|
int_solver * m_int_solver;
|
|
bool m_need_register_terms;
|
|
var_register m_var_register;
|
|
var_register m_term_register;
|
|
stacked_vector<ul_pair> m_columns_to_ul_pairs;
|
|
constraint_set m_constraints;
|
|
// the set of column indices j such that bounds have changed for j
|
|
u_set m_columns_with_changed_bounds;
|
|
u_set m_rows_with_changed_bounds;
|
|
u_set m_basic_columns_with_changed_cost;
|
|
// these are basic columns with the value changed, so the the corresponding row in the tableau
|
|
// does not sum to zero anymore
|
|
u_set m_incorrect_columns;
|
|
stacked_value<unsigned> m_term_count;
|
|
vector<lar_term*> m_terms;
|
|
indexed_vector<mpq> m_column_buffer;
|
|
std::unordered_map<lar_term, std::pair<mpq, unsigned>, term_hasher, term_comparer>
|
|
m_normalized_terms_to_columns;
|
|
vector<impq> m_backup_x;
|
|
stacked_vector<unsigned> m_usage_in_terms;
|
|
// ((x[j], is_int(j))->j) for fixed j, used in equalities propagation
|
|
// maps values to integral fixed vars
|
|
map<mpq, unsigned, obj_hash<mpq>, default_eq<mpq>> m_fixed_var_table_int;
|
|
// maps values to non-integral fixed vars
|
|
map<mpq, unsigned, obj_hash<mpq>, default_eq<mpq>> m_fixed_var_table_real;
|
|
// end of fields
|
|
|
|
////////////////// methods ////////////////////////////////
|
|
static_matrix<double, double> & A_d();
|
|
static_matrix<double, double > const & A_d() const;
|
|
|
|
static bool valid_index(unsigned j) { return static_cast<int>(j) >= 0;}
|
|
const lar_term & get_term(unsigned j) const;
|
|
bool row_has_a_big_num(unsigned i) const;
|
|
// init region
|
|
bool strategy_is_undecided() const;
|
|
void register_new_ext_var_index(unsigned ext_v, bool is_int);
|
|
bool term_is_int(const lar_term * t) const;
|
|
bool term_is_int(const vector<std::pair<mpq, unsigned int>> & coeffs) const;
|
|
void add_non_basic_var_to_core_fields(unsigned ext_j, bool is_int);
|
|
void add_new_var_to_core_fields_for_doubles(bool register_in_basis);
|
|
void add_new_var_to_core_fields_for_mpq(bool register_in_basis);
|
|
mpq adjust_bound_for_int(lpvar j, lconstraint_kind&, const mpq&);
|
|
|
|
// terms
|
|
bool all_vars_are_registered(const vector<std::pair<mpq, var_index>> & coeffs);
|
|
var_index add_term_undecided(const vector<std::pair<mpq, var_index>> & coeffs);
|
|
bool term_coeffs_are_ok(const vector<std::pair<mpq, var_index>> & coeffs);
|
|
void push_term(lar_term* t);
|
|
void add_row_for_term(const lar_term * term, unsigned term_ext_index);
|
|
void add_row_from_term_no_constraint(const lar_term * term, unsigned term_ext_index);
|
|
void add_basic_var_to_core_fields();
|
|
bool compare_values(impq const& lhs, lconstraint_kind k, const mpq & rhs);
|
|
|
|
inline void clear_columns_with_changed_bounds() { m_columns_with_changed_bounds.clear(); }
|
|
inline void increase_by_one_columns_with_changed_bounds() { m_columns_with_changed_bounds.increase_size_by_one(); }
|
|
inline void insert_to_columns_with_changed_bounds(unsigned j) {
|
|
m_columns_with_changed_bounds.insert(j);
|
|
}
|
|
|
|
|
|
void update_column_type_and_bound_check_on_equal(unsigned j, lconstraint_kind kind, const mpq & right_side, constraint_index constr_index, unsigned&);
|
|
void update_column_type_and_bound(unsigned j, lconstraint_kind kind, const mpq & right_side, constraint_index constr_index);
|
|
void update_column_type_and_bound_with_ub(var_index j, lconstraint_kind kind, const mpq & right_side, constraint_index constr_index);
|
|
void update_column_type_and_bound_with_no_ub(var_index j, lconstraint_kind kind, const mpq & right_side, constraint_index constr_index);
|
|
void update_bound_with_ub_lb(var_index j, lconstraint_kind kind, const mpq & right_side, constraint_index constr_index);
|
|
void update_bound_with_no_ub_lb(var_index j, lconstraint_kind kind, const mpq & right_side, constraint_index constr_index);
|
|
void update_bound_with_ub_no_lb(var_index j, lconstraint_kind kind, const mpq & right_side, constraint_index constr_index);
|
|
void update_bound_with_no_ub_no_lb(var_index j, lconstraint_kind kind, const mpq & right_side, constraint_index constr_index);
|
|
void register_in_fixed_var_table(unsigned, unsigned&);
|
|
void remove_non_fixed_from_fixed_var_table();
|
|
constraint_index add_var_bound_on_constraint_for_term(var_index j, lconstraint_kind kind, const mpq & right_side);
|
|
inline void set_infeasible_column(unsigned j) {
|
|
set_status(lp_status::INFEASIBLE);
|
|
m_crossed_bounds_column = j;
|
|
}
|
|
constraint_index add_constraint_from_term_and_create_new_column_row(unsigned term_j, const lar_term* term,
|
|
lconstraint_kind kind, const mpq & right_side);
|
|
unsigned row_of_basic_column(unsigned) const;
|
|
void decide_on_strategy_and_adjust_initial_state();
|
|
void adjust_initial_state();
|
|
void adjust_initial_state_for_lu();
|
|
void adjust_initial_state_for_tableau_rows();
|
|
void fill_last_row_of_A_d(static_matrix<double, double> & A, const lar_term* ls);
|
|
void clear();
|
|
bool use_lu() const;
|
|
bool sizes_are_correct() const;
|
|
bool implied_bound_is_correctly_explained(implied_bound const & be, const vector<std::pair<mpq, unsigned>> & explanation) const;
|
|
|
|
template <typename T>
|
|
void analyze_new_bounds_on_row_tableau(
|
|
unsigned row_index,
|
|
lp_bound_propagator<T> & bp ) {
|
|
|
|
if (A_r().m_rows[row_index].size() > settings().max_row_length_for_bound_propagation
|
|
|| row_has_a_big_num(row_index))
|
|
return;
|
|
lp_assert(use_tableau());
|
|
|
|
bound_analyzer_on_row<row_strip<mpq>, lp_bound_propagator<T>>::analyze_row(A_r().m_rows[row_index],
|
|
null_ci,
|
|
zero_of_type<numeric_pair<mpq>>(),
|
|
row_index,
|
|
bp
|
|
);
|
|
}
|
|
|
|
void substitute_basis_var_in_terms_for_row(unsigned i);
|
|
template <typename T>
|
|
void calculate_implied_bounds_for_row(unsigned i, lp_bound_propagator<T> & bp) {
|
|
SASSERT(use_tableau());
|
|
analyze_new_bounds_on_row_tableau(i, bp);
|
|
}
|
|
static void clean_popped_elements(unsigned n, u_set& set);
|
|
static void shrink_inf_set_after_pop(unsigned n, u_set & set);
|
|
bool maximize_term_on_tableau(const lar_term & term,
|
|
impq &term_max);
|
|
bool costs_are_zeros_for_r_solver() const;
|
|
bool reduced_costs_are_zeroes_for_r_solver() const;
|
|
void set_costs_to_zero(const lar_term & term);
|
|
void prepare_costs_for_r_solver(const lar_term & term);
|
|
bool maximize_term_on_corrected_r_solver(lar_term & term, impq &term_max);
|
|
void pop_core_solver_params();
|
|
void pop_core_solver_params(unsigned k);
|
|
void set_upper_bound_witness(var_index j, constraint_index ci);
|
|
void set_lower_bound_witness(var_index j, constraint_index ci);
|
|
void substitute_terms_in_linear_expression( const vector<std::pair<mpq, var_index>>& left_side_with_terms,
|
|
vector<std::pair<mpq, var_index>> &left_side) const;
|
|
void detect_rows_of_bound_change_column_for_nbasic_column(unsigned j);
|
|
void detect_rows_of_bound_change_column_for_nbasic_column_tableau(unsigned j);
|
|
bool use_tableau() const;
|
|
bool use_tableau_costs() const;
|
|
void detect_rows_of_column_with_bound_change(unsigned j);
|
|
void adjust_x_of_column(unsigned j);
|
|
bool tableau_with_costs() const;
|
|
bool costs_are_used() const;
|
|
void change_basic_columns_dependend_on_a_given_nb_column(unsigned j, const numeric_pair<mpq> & delta);
|
|
void update_x_and_inf_costs_for_column_with_changed_bounds(unsigned j);
|
|
unsigned num_changed_bounds() const { return m_rows_with_changed_bounds.size(); }
|
|
void detect_rows_with_changed_bounds_for_column(unsigned j);
|
|
void detect_rows_with_changed_bounds();
|
|
void set_value_for_nbasic_column(unsigned j, const impq & new_val);
|
|
void update_x_and_inf_costs_for_columns_with_changed_bounds();
|
|
void update_x_and_inf_costs_for_columns_with_changed_bounds_tableau();
|
|
void solve_with_core_solver();
|
|
numeric_pair<mpq> get_basic_var_value_from_row(unsigned i);
|
|
template <typename K, typename L>
|
|
void add_last_rows_to_lu(lp_primal_core_solver<K,L> & s);
|
|
bool x_is_correct() const;
|
|
void fill_last_row_of_A_r(static_matrix<mpq, numeric_pair<mpq>> & A, const lar_term * ls);
|
|
template <typename U, typename V>
|
|
void create_matrix_A(static_matrix<U, V> & matr);
|
|
template <typename U, typename V>
|
|
void copy_from_mpq_matrix(static_matrix<U, V> & matr);
|
|
bool try_to_set_fixed(column_info<mpq> & ci);
|
|
bool all_constrained_variables_are_registered(const vector<std::pair<mpq, var_index>>& left_side);
|
|
bool all_constraints_hold() const;
|
|
bool constraint_holds(const lar_base_constraint & constr, std::unordered_map<var_index, mpq> & var_map) const;
|
|
bool the_relations_are_of_same_type(const vector<std::pair<mpq, unsigned>> & evidence, lconstraint_kind & the_kind_of_sum) const;
|
|
static void register_in_map(std::unordered_map<var_index, mpq> & coeffs, const lar_base_constraint & cn, const mpq & a);
|
|
static void register_monoid_in_map(std::unordered_map<var_index, mpq> & coeffs, const mpq & a, unsigned j);
|
|
bool the_left_sides_sum_to_zero(const vector<std::pair<mpq, unsigned>> & evidence) const;
|
|
bool the_right_sides_do_not_sum_to_zero(const vector<std::pair<mpq, unsigned>> & evidence);
|
|
bool explanation_is_correct(explanation&) const;
|
|
bool inf_explanation_is_correct() const;
|
|
mpq sum_of_right_sides_of_explanation(explanation &) const;
|
|
void get_infeasibility_explanation_for_inf_sign(
|
|
explanation & exp,
|
|
const vector<std::pair<mpq, unsigned>> & inf_row,
|
|
int inf_sign) const;
|
|
mpq get_left_side_val(const lar_base_constraint & cns, const std::unordered_map<var_index, mpq> & var_map) const;
|
|
void fill_var_set_for_random_update(unsigned sz, var_index const * vars, vector<unsigned>& column_list);
|
|
void pivot_fixed_vars_from_basis();
|
|
bool column_represents_row_in_tableau(unsigned j);
|
|
void make_sure_that_the_bottom_right_elem_not_zero_in_tableau(unsigned i, unsigned j);
|
|
void remove_last_row_and_column_from_tableau(unsigned j);
|
|
void remove_last_column_from_A();
|
|
|
|
void remove_last_column_from_basis_tableau(unsigned j);
|
|
void remove_last_column_from_tableau();
|
|
void pop_tableau();
|
|
void clean_inf_set_of_r_solver_after_pop();
|
|
void shrink_explanation_to_minimum(vector<std::pair<mpq, constraint_index>> & explanation) const;
|
|
inline bool column_value_is_integer(unsigned j) const { return get_column_value(j).is_int(); }
|
|
bool model_is_int_feasible() const;
|
|
inline
|
|
indexed_vector<mpq> & get_column_in_lu_mode(unsigned j) {
|
|
m_column_buffer.clear();
|
|
m_column_buffer.resize(A_r().row_count());
|
|
m_mpq_lar_core_solver.m_r_solver.solve_Bd(j, m_column_buffer);
|
|
return m_column_buffer;
|
|
}
|
|
bool bound_is_integer_for_integer_column(unsigned j, const mpq & right_side) const;
|
|
inline unsigned get_base_column_in_row(unsigned row_index) const {
|
|
return m_mpq_lar_core_solver.m_r_solver.get_base_column_in_row(row_index);
|
|
}
|
|
inline lar_core_solver & get_core_solver() { return m_mpq_lar_core_solver; }
|
|
void catch_up_in_updating_int_solver();
|
|
var_index to_column(unsigned ext_j) const;
|
|
void fix_terms_with_rounded_columns();
|
|
void update_delta_for_terms(const impq & delta, unsigned j, const vector<unsigned>&);
|
|
void fill_vars_to_terms(vector<vector<unsigned>> & vars_to_terms);
|
|
bool remove_from_basis(unsigned);
|
|
lar_term get_term_to_maximize(unsigned ext_j) const;
|
|
bool sum_first_coords(const lar_term& t, mpq & val) const;
|
|
void collect_rounded_rows_to_fix();
|
|
void register_normalized_term(const lar_term&, lpvar);
|
|
void deregister_normalized_term(const lar_term&);
|
|
public:
|
|
const map<mpq, unsigned, obj_hash<mpq>, default_eq<mpq>>& fixed_var_table_int() const {
|
|
return m_fixed_var_table_int;
|
|
}
|
|
map<mpq, unsigned, obj_hash<mpq>, default_eq<mpq>>& fixed_var_table_int() {
|
|
return m_fixed_var_table_int;
|
|
}
|
|
const map<mpq, unsigned, obj_hash<mpq>, default_eq<mpq>>& fixed_var_table_real() const {
|
|
return m_fixed_var_table_real;
|
|
}
|
|
map<mpq, unsigned, obj_hash<mpq>, default_eq<mpq>>& fixed_var_table_real() {
|
|
return m_fixed_var_table_real;
|
|
}
|
|
|
|
bool find_in_fixed_tables(const rational& mpq, bool is_int, unsigned & j) const {
|
|
return is_int? fixed_var_table_int().find(mpq, j) :
|
|
fixed_var_table_real().find(mpq, j);
|
|
}
|
|
|
|
template <typename T> void remove_non_fixed_from_table(T&);
|
|
unsigned external_to_column_index(unsigned) const;
|
|
bool inside_bounds(lpvar, const impq&) const;
|
|
inline void set_column_value(unsigned j, const impq& v) {
|
|
m_mpq_lar_core_solver.m_r_solver.update_x(j, v);
|
|
}
|
|
inline void set_column_value_test(unsigned j, const impq& v) {
|
|
set_column_value(j, v);
|
|
}
|
|
unsigned get_total_iterations() const;
|
|
var_index add_named_var(unsigned ext_j, bool is_integer, const std::string&);
|
|
lp_status maximize_term(unsigned j_or_term, impq &term_max);
|
|
inline
|
|
core_solver_pretty_printer<lp::mpq, lp::impq> pp(std::ostream& out) const { return
|
|
core_solver_pretty_printer<lp::mpq, lp::impq>(m_mpq_lar_core_solver.m_r_solver, out); }
|
|
void get_infeasibility_explanation(explanation &) const;
|
|
inline void backup_x() { m_backup_x = m_mpq_lar_core_solver.m_r_x; }
|
|
inline void restore_x() { m_mpq_lar_core_solver.m_r_x = m_backup_x; }
|
|
template <typename T>
|
|
void explain_implied_bound(const implied_bound & ib, lp_bound_propagator<T> & bp) {
|
|
unsigned i = ib.m_row_or_term_index;
|
|
int bound_sign = ib.m_is_lower_bound? 1: -1;
|
|
int j_sign = (ib.m_coeff_before_j_is_pos ? 1 :-1) * bound_sign;
|
|
unsigned bound_j = ib.m_j;
|
|
if (tv::is_term(bound_j)) {
|
|
bound_j = m_var_register.external_to_local(bound_j);
|
|
}
|
|
for (auto const& r : A_r().m_rows[i]) {
|
|
unsigned j = r.var();
|
|
if (j == bound_j) continue;
|
|
mpq const& a = r.coeff();
|
|
int a_sign = is_pos(a)? 1: -1;
|
|
int sign = j_sign * a_sign;
|
|
const ul_pair & ul = m_columns_to_ul_pairs[j];
|
|
auto witness = sign > 0? ul.upper_bound_witness(): ul.lower_bound_witness();
|
|
lp_assert(is_valid(witness));
|
|
bp.consume(a, witness);
|
|
}
|
|
}
|
|
// lp_assert(implied_bound_is_correctly_explained(ib, explanation)); }
|
|
constraint_index mk_var_bound(var_index j, lconstraint_kind kind, const mpq & right_side);
|
|
void activate_check_on_equal(constraint_index, var_index&);
|
|
void activate(constraint_index);
|
|
void random_update(unsigned sz, var_index const * vars);
|
|
void mark_rows_for_bound_prop(lpvar j);
|
|
template <typename T>
|
|
void propagate_bounds_for_touched_rows(lp_bound_propagator<T> & bp) {
|
|
SASSERT(use_tableau());
|
|
for (unsigned i : m_rows_with_changed_bounds) {
|
|
calculate_implied_bounds_for_row(i, bp);
|
|
if (settings().get_cancel_flag())
|
|
return;
|
|
}
|
|
// these two loops should be run sequentially
|
|
// since the first loop might change column bounds
|
|
// and add fixed columns this way
|
|
bp.clear_for_eq();
|
|
if (settings().cheap_eqs()) {
|
|
for (unsigned i : m_rows_with_changed_bounds) {
|
|
calculate_cheap_eqs_for_row(i, bp);
|
|
if (settings().get_cancel_flag())
|
|
return;
|
|
}
|
|
}
|
|
m_rows_with_changed_bounds.clear();
|
|
}
|
|
template <typename T>
|
|
void calculate_cheap_eqs_for_row(unsigned i, lp_bound_propagator<T> & bp) {
|
|
bp.cheap_eq_tree(i);
|
|
}
|
|
|
|
bool is_fixed(column_index const& j) const { return column_is_fixed(j); }
|
|
inline column_index to_column_index(unsigned v) const { return column_index(external_to_column_index(v)); }
|
|
bool external_is_used(unsigned) const;
|
|
void pop(unsigned k);
|
|
bool compare_values(var_index j, lconstraint_kind kind, const mpq & right_side);
|
|
var_index add_term(const vector<std::pair<mpq, var_index>> & coeffs, unsigned ext_i);
|
|
void register_existing_terms();
|
|
constraint_index add_var_bound(var_index, lconstraint_kind, const mpq &);
|
|
constraint_index add_var_bound_check_on_equal(var_index, lconstraint_kind, const mpq &, var_index&);
|
|
|
|
var_index add_var(unsigned ext_j, bool is_integer);
|
|
void set_cut_strategy(unsigned cut_frequency);
|
|
inline unsigned column_count() const { return A_r().column_count(); }
|
|
inline var_index local_to_external(var_index idx) const {
|
|
return tv::is_term(idx)?
|
|
m_term_register.local_to_external(idx) : m_var_register.local_to_external(idx);
|
|
}
|
|
bool column_corresponds_to_term(unsigned) const;
|
|
inline unsigned row_count() const { return A_r().row_count(); }
|
|
bool var_is_registered(var_index vj) const;
|
|
void clear_inf_set() {
|
|
m_mpq_lar_core_solver.m_r_solver.inf_set().clear();
|
|
}
|
|
inline void remove_column_from_inf_set(unsigned j) {
|
|
m_mpq_lar_core_solver.m_r_solver.remove_column_from_inf_set(j);
|
|
}
|
|
template <typename ChangeReport>
|
|
void change_basic_columns_dependend_on_a_given_nb_column_report(unsigned j,
|
|
const numeric_pair<mpq> & delta,
|
|
const ChangeReport& after) {
|
|
if (use_tableau()) {
|
|
for (const auto & c : A_r().m_columns[j]) {
|
|
unsigned bj = m_mpq_lar_core_solver.m_r_basis[c.var()];
|
|
if (tableau_with_costs()) {
|
|
m_basic_columns_with_changed_cost.insert(bj);
|
|
}
|
|
m_mpq_lar_core_solver.m_r_solver.add_delta_to_x_and_track_feasibility(bj, - A_r().get_val(c) * delta);
|
|
after(bj);
|
|
TRACE("change_x_del",
|
|
tout << "changed basis column " << bj << ", it is " <<
|
|
( m_mpq_lar_core_solver.m_r_solver.column_is_feasible(bj)? "feas":"inf") << std::endl;);
|
|
|
|
|
|
}
|
|
} else {
|
|
NOT_IMPLEMENTED_YET();
|
|
m_column_buffer.clear();
|
|
m_column_buffer.resize(A_r().row_count());
|
|
m_mpq_lar_core_solver.m_r_solver.solve_Bd(j, m_column_buffer);
|
|
for (unsigned i : m_column_buffer.m_index) {
|
|
unsigned bj = m_mpq_lar_core_solver.m_r_basis[i];
|
|
m_mpq_lar_core_solver.m_r_solver.add_delta_to_x_and_track_feasibility(bj, -m_column_buffer[i] * delta);
|
|
}
|
|
}
|
|
}
|
|
|
|
template <typename ChangeReport>
|
|
void set_value_for_nbasic_column_report(unsigned j,
|
|
const impq & new_val,
|
|
const ChangeReport& after) {
|
|
|
|
lp_assert(!is_base(j));
|
|
auto & x = m_mpq_lar_core_solver.m_r_x[j];
|
|
auto delta = new_val - x;
|
|
x = new_val;
|
|
after(j);
|
|
change_basic_columns_dependend_on_a_given_nb_column_report(j, delta, after);
|
|
}
|
|
|
|
template <typename Blocker, typename ChangeReport>
|
|
bool try_to_patch(lpvar j, const mpq& val,
|
|
const Blocker& is_blocked,
|
|
const ChangeReport& change_report) {
|
|
if (is_base(j)) {
|
|
TRACE("nla_solver", get_int_solver()->display_row_info(tout, row_of_basic_column(j)) << "\n";);
|
|
remove_from_basis(j);
|
|
}
|
|
|
|
impq ival(val);
|
|
if (is_blocked(j, ival))
|
|
return false;
|
|
TRACE("nla_solver", tout << "j" << j << " not blocked\n";);
|
|
impq delta = get_column_value(j) - ival;
|
|
for (const auto &c : A_r().column(j)) {
|
|
unsigned row_index = c.var();
|
|
const mpq & a = c.coeff();
|
|
unsigned rj = m_mpq_lar_core_solver.m_r_basis[row_index];
|
|
impq rj_new_val = a * delta + get_column_value(rj);
|
|
// if (column_is_int(rj) && !rj_new_val.is_int())
|
|
// return false;
|
|
if (is_blocked(rj, rj_new_val))
|
|
return false;
|
|
}
|
|
|
|
set_value_for_nbasic_column_report(j, ival, change_report);
|
|
return true;
|
|
}
|
|
inline bool column_has_upper_bound(unsigned j) const {
|
|
return m_mpq_lar_core_solver.m_r_solver.column_has_upper_bound(j);
|
|
}
|
|
|
|
inline bool column_has_lower_bound(unsigned j) const {
|
|
return m_mpq_lar_core_solver.m_r_solver.column_has_lower_bound(j);
|
|
}
|
|
|
|
inline
|
|
constraint_index get_column_upper_bound_witness(unsigned j) const {
|
|
if (tv::is_term(j)) {
|
|
j = m_var_register.external_to_local(j);
|
|
}
|
|
return m_columns_to_ul_pairs()[j].upper_bound_witness();
|
|
}
|
|
|
|
inline
|
|
const impq& get_upper_bound(column_index j) const {
|
|
return m_mpq_lar_core_solver.m_r_solver.m_upper_bounds[j];
|
|
}
|
|
|
|
inline
|
|
const impq& get_lower_bound(column_index j) const {
|
|
return m_mpq_lar_core_solver.m_r_solver.m_lower_bounds[j];
|
|
}
|
|
bool has_lower_bound(var_index var, constraint_index& ci, mpq& value, bool& is_strict) const;
|
|
bool has_upper_bound(var_index var, constraint_index& ci, mpq& value, bool& is_strict) const;
|
|
bool has_value(var_index var, mpq& value) const;
|
|
bool fetch_normalized_term_column(const lar_term& t, std::pair<mpq, lpvar>& ) const;
|
|
unsigned map_term_index_to_column_index(unsigned j) const;
|
|
bool column_is_fixed(unsigned j) const;
|
|
bool column_is_free(unsigned j) const;
|
|
unsigned column_to_reported_index(unsigned j) const;
|
|
lp_settings & settings();
|
|
lp_settings const & settings() const;
|
|
column_type get_column_type(unsigned j) const { return m_mpq_lar_core_solver.m_column_types()[j]; }
|
|
const impq & get_lower_bound(unsigned j) const { return m_mpq_lar_core_solver.m_r_lower_bounds()[j]; }
|
|
const impq & get_upper_bound(unsigned j) const { return m_mpq_lar_core_solver.m_r_upper_bounds()[j]; }
|
|
std::ostream& print_terms(std::ostream& out) const;
|
|
std::ostream& print_term(lar_term const& term, std::ostream & out) const;
|
|
static std::ostream& print_term_as_indices(lar_term const& term, std::ostream & out);
|
|
std::ostream& print_constraint_indices_only(const lar_base_constraint * c, std::ostream & out) const;
|
|
std::ostream& print_implied_bound(const implied_bound& be, std::ostream & out) const;
|
|
std::ostream& print_values(std::ostream& out) const;
|
|
void get_model(std::unordered_map<var_index, mpq> & variable_values) const;
|
|
void get_rid_of_inf_eps();
|
|
void get_model_do_not_care_about_diff_vars(std::unordered_map<var_index, mpq> & variable_values) const;
|
|
std::string get_variable_name(var_index vi) const;
|
|
void set_variable_name(var_index vi, std::string);
|
|
inline unsigned number_of_vars() const { return m_var_register.size(); }
|
|
inline bool is_base(unsigned j) const { return m_mpq_lar_core_solver.m_r_heading[j] >= 0; }
|
|
inline const impq & column_lower_bound(unsigned j) const {
|
|
return m_mpq_lar_core_solver.lower_bound(j);
|
|
}
|
|
|
|
void pivot_column_tableau(unsigned j, unsigned row_index);
|
|
|
|
inline const impq & column_upper_bound(unsigned j) const {
|
|
return m_mpq_lar_core_solver.upper_bound(j);
|
|
}
|
|
|
|
inline bool column_is_bounded(unsigned j) const {
|
|
return m_mpq_lar_core_solver.column_is_bounded(j);
|
|
}
|
|
|
|
std::pair<constraint_index, constraint_index> add_equality(lpvar j, lpvar k);
|
|
|
|
inline void get_bound_constraint_witnesses_for_column(unsigned j, constraint_index & lc, constraint_index & uc) const {
|
|
const ul_pair & ul = m_columns_to_ul_pairs[j];
|
|
lc = ul.lower_bound_witness();
|
|
uc = ul.upper_bound_witness();
|
|
}
|
|
inline constraint_set const& constraints() const { return m_constraints; }
|
|
void push();
|
|
void pop();
|
|
inline constraint_index get_column_lower_bound_witness(unsigned j) const {
|
|
if (tv::is_term(j)) {
|
|
j = m_var_register.external_to_local(j);
|
|
}
|
|
return m_columns_to_ul_pairs()[j].lower_bound_witness();
|
|
}
|
|
|
|
inline tv column2tv(column_index const& c) const {
|
|
return tv::raw(column_to_reported_index(c));
|
|
}
|
|
|
|
inline std::ostream& print_column_info(unsigned j, std::ostream& out) const {
|
|
m_mpq_lar_core_solver.m_r_solver.print_column_info(j, out);
|
|
if (tv::is_term(j)) {
|
|
print_term_as_indices(get_term(j), out) << "\n";
|
|
|
|
} else if (column_corresponds_to_term(j)) {
|
|
const lar_term& t = get_term(m_var_register.local_to_external(j));
|
|
print_term_as_indices(t, out) << "\n";
|
|
}
|
|
return out;
|
|
}
|
|
|
|
inline std::ostream& print_column_bound_info(unsigned j, std::ostream& out) const {
|
|
return m_mpq_lar_core_solver.m_r_solver.print_column_bound_info(j, out);
|
|
}
|
|
|
|
bool has_int_var() const;
|
|
|
|
inline bool has_inf_int() const {
|
|
for (unsigned j = 0; j < column_count(); j++) {
|
|
if (column_is_int(j) && ! column_value_is_int(j))
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
inline const vector<lar_term*> & terms() const { return m_terms; }
|
|
inline lar_term const& term(unsigned i) const { return *m_terms[i]; }
|
|
inline void set_int_solver(int_solver * int_slv) { m_int_solver = int_slv; }
|
|
inline int_solver * get_int_solver() { return m_int_solver; }
|
|
inline const int_solver * get_int_solver() const { return m_int_solver; }
|
|
inline const lar_term & get_term(tv const& t) const { lp_assert(t.is_term()); return *m_terms[t.id()]; }
|
|
lp_status find_feasible_solution();
|
|
void move_non_basic_columns_to_bounds(bool);
|
|
bool move_non_basic_column_to_bounds(unsigned j, bool);
|
|
inline bool r_basis_has_inf_int() const {
|
|
for (unsigned j : r_basis()) {
|
|
if (column_is_int(j) && ! column_value_is_int(j))
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
void round_to_integer_solution();
|
|
inline const row_strip<mpq> & get_row(unsigned i) const { return A_r().m_rows[i]; }
|
|
inline const column_strip & get_column(unsigned i) const { return A_r().m_columns[i]; }
|
|
bool row_is_correct(unsigned i) const;
|
|
bool ax_is_correct() const;
|
|
bool get_equality_and_right_side_for_term_on_current_x(tv const& t, mpq &rs, constraint_index& ci, bool &upper_bound) const;
|
|
bool var_is_int(var_index v) const;
|
|
inline const vector<int> & r_heading() const { return m_mpq_lar_core_solver.m_r_heading; }
|
|
inline const vector<unsigned> & r_basis() const { return m_mpq_lar_core_solver.r_basis(); }
|
|
inline const vector<unsigned> & r_nbasis() const { return m_mpq_lar_core_solver.r_nbasis(); }
|
|
inline bool column_is_real(unsigned j) const { return !column_is_int(j); }
|
|
lp_status get_status() const;
|
|
void set_status(lp_status s);
|
|
lp_status solve();
|
|
void fill_explanation_from_crossed_bounds_column(explanation & evidence) const;
|
|
bool term_is_used_as_row(unsigned term) const;
|
|
bool tighten_term_bounds_by_delta(tv const& t, const impq&);
|
|
lar_solver();
|
|
void set_track_pivoted_rows(bool v);
|
|
bool get_track_pivoted_rows() const;
|
|
virtual ~lar_solver();
|
|
const vector<impq>& r_x() const { return m_mpq_lar_core_solver.m_r_x; }
|
|
bool column_is_int(unsigned j) const;
|
|
inline bool column_value_is_int(unsigned j) const { return m_mpq_lar_core_solver.m_r_x[j].is_int(); }
|
|
inline static_matrix<mpq, impq> & A_r() { return m_mpq_lar_core_solver.m_r_A; }
|
|
inline const static_matrix<mpq, impq> & A_r() const { return m_mpq_lar_core_solver.m_r_A; }
|
|
// columns
|
|
bool column_is_int(column_index const& j) const { return column_is_int((unsigned)j); }
|
|
const impq& get_value(column_index const& j) const { return get_column_value(j); }
|
|
const impq& get_column_value(unsigned j) const { return m_mpq_lar_core_solver.m_r_x[j]; }
|
|
inline
|
|
var_index external_to_local(unsigned j) const {
|
|
var_index local_j;
|
|
if (m_var_register.external_is_used(j, local_j) ||
|
|
m_term_register.external_is_used(j, local_j)) {
|
|
return local_j;
|
|
}
|
|
else {
|
|
return -1;
|
|
}
|
|
}
|
|
unsigned usage_in_terms(column_index j) const {
|
|
if (j >= m_usage_in_terms.size())
|
|
return 0;
|
|
return m_usage_in_terms[j];
|
|
}
|
|
friend int_solver;
|
|
friend int_branch;
|
|
|
|
};
|
|
}
|